Swirl chamber for diesel engines and the like

Abstract

A dome shaped ceramic insert which defines a portion of a swirl chamber is formed at the crown portion with a single aperture through which both the fuel injector and the glow plug can extend. The cylinder head is formed with a portion which fits into the aperture and which has a wall portion which cooperates with the inner walls of the insert to define the upper section of the swirl chamber.

What is claimed is: 
     
       1. In a swirl chamber type internal combustion engine a thermally insulating member disposed in a recess formed in a metallic cylinder head, said insulating member including a cavity which defines a portion of said swirl chamber;   means defining an aperture in said insulating member; and   means defining a metallic projection which fits into said aperture, said projection including first and second bores, said first and second bores being arranged to receive first and second devices.   
     
     
       2. An engine as claimed in claim 1 wherein said first and second devices comprise a fuel injector and a glow plug. 
     
     
       3. An engine as claimed in claim 1 furher comprising a second thermally insulating member disposed in said recess, said second insulating member having a cavity which cooperates with the cavity formed in the first said insulating member to define said swirl chamber. 
     
     
       4. An engine as claimed in claim 1 wherein said insulating member has an essentially dome shape and wherein said aperture is formed proximate the the crown portion of the dome shape. 
     
     
       5. An engine as claimed in claim 1 wherein said aperture is essentially circular. 
     
     
       6. An engine as claimed in claim 1 wherein said aperture has a shape which tends to minimize the area thereof. 
     
     
       7. An engine as claimed in claim 3 wherein the first said insulating member is disposed in a blind end of said recess and said second insulating member is disposed in an opening end of said recess in a manner which retains the first said insulating member snugly in position. 
     
     
       8. In an engine; a cylinder defined in a cylinder block;   a piston reciprocatively disposed in said cylinder   a cylinder head secured to said cylinder block in a manner to close the cylinder and to define a main variable volume combustion chamber, said cylinder head being formed of a metal and including a recess;   a thermally insulating member disposed in said recess, said insulating member forming a portion of a swirl chamber which is fluidly communicated with said main variable volume combustion chamber; and   means defining a single opening in said insulating member through which a fuel injector and a glow plug extend operatively into said swirl chamber.